The purpose of the Pathology Core is to provide large-scale histopathological, immunohistochemical (IHC), and in situ RNA evaluation of breast and ovarian tissue to all 3 projects of this proposal. Histopathology, IHC, and in situ RNA analysis play a central role in the experimental designs of all these projects. Breast histopathology, IHC, and Tunel assays for apoptosis will be carried out at the UTHSCSA component of the Core, while ovarian histopathology and IHC as well as in situ hybridization studies will be performed at the MDACC component. Overall, this effort will involve cutting, staining, and (most importantly) interpreting nearly 10,000 slides. We feel that this Core is necessary to ensure cost efficiency and uniformity of results for this large workload. We have the necessary laboratory space, equipment, and human resources to make this centralized approach work successfully.